#include <stdio.h>
union student 
{
    char a;
    int b;
    short c;
};
struct stu
{
    char a;
    int b;
    short c;
};
int main(int argc, char const *argv[])
{
    struct stu st;
    union student su; 
    printf("sizeof(struct) : %d \n", sizeof(st));
    printf("sizeof(union) : %d \n", sizeof(su));// 所需要的内存为最大的共用内存
    return 0;
}
